Metabolism, bioactions and physiological significance of 2-arachidonoylglycerol, a novel lipid mediator

1. 2-花生四烯酰基甘油（2-AG）新型类似物的研制。在这项研究中，首先，我们开发了几种代谢稳定的2-AG类似物。这些类似物将为阐明2- ag2可能的生物活性提供有用的工具。脑内2-AG的生成及其生理意义。接下来，我们研究了大鼠脑突触体中2-AG的合成。我们发现2-AG水平在去极化突触体中显著增加。我们发现30%的新形成的2-AG从去极化突触体中释放出来，这表明2-AG可以作为细胞间介质。接下来，我们研究了SR141716A对去极化突触体释放谷氨酸的影响。我们发现用SR141716A处理突触体可以显著增强突触体去极化时谷氨酸的释放。这些结果强烈提示，受刺激的神经元释放的2-AG可能在ne的衰减中具有重要的生理作用，更多的是通过作用于主要在突触前表达的CB1受体来传递。2-AG在免疫系统中的生理意义。我们发现2-AG在HL-60细胞中诱导p42/44 MAP激酶的快速磷酸化和激活。除了p42/44 MAP激酶外，我们发现在2- ag刺激的HL-60细胞中，p38MAP激酶和c-Jun n末端激酶也发生了快速磷酸化。我们还发现2-AG诱导HL-60细胞向巨噬细胞样细胞的迁移。经SR144528或PTX预处理后，2- ag诱导的HL-60细胞迁移能力明显减弱，表明迁移是通过CB2受体和Gi/Go介导的。我们还发现，将2-AG添加到HL-60细胞中，可以通过CB2受体和Gi/ go依赖机制增强IL-8和MCP- 1等趋化因子的产生。基于细胞迁移和趋化因子产生的实验结果，我们提出2-AG在炎症反应和免疫反应中具有积极而非消极的作用。少

1. Development of novel analogs of 2-arachidonoylglycerol (2-AG). In this study, first, we have developed several metabolically stable analogs of 2-AG. These analogs would be useful tools in the elucidation of the possible biological activities of 2-AG.2. The generation of 2-AG in the brain and its physiological meanings. Next, we examined the synthesis of 2-AG in rat brain synaptosomes. We found that the level of 2-AG was augmented markedly in depolarized synaptosomes. We found that 30 % of newly formed 2-AG was released from depolarized synaptosomes, indicating that 2-AG can act as an intercellular mediator. Next, we examined the effect of SR141716A on the release of glutamate from depolarized synaptosomes. We found that treatment of synaptosomes with SR141716A significantly enhanced the release of glutamate from synaptosomes upon depolarization. These results strongly suggest that 2-AG released from stimulated neurons may have an important physiological role in the attenuation of ne … More urotransmission through acting on the CB1 receptor expressed mainly in the presynapse.3. Physiological meanings of 2-AG in the immune system. We found that 2-AG induces rapid phosphorylation and activation of the p42/44 MAP kinase in HL-60 cells. In addition to the p42/44 MAP kinase, we found that rapid phosphorylation of the p38MAP kinase and c-Jun N-terminal kinase takes place in 2-AG-stimulated HL-60 cells. We also found that 2-AG induces the migration of HL-60 cells differentiated into macrophage-like cells. The 2-AG-induced migration of HL-60 cells was markedly reduced when the cells were pretreated with either SR144528 or PTX, suggesting that the migration was mediated through the CB2 receptor and Gi/Go. We also found that the addition of 2-AG to HL-60 cells enhanced the production of chemokines such as IL-8 and MCP- 1 through a CB2 receptor- and Gi/Go-dependent mechanism. Based on the experimental results concerning cell migration and chemokine production, we propose that 2-AG has a positive rather than negative role during inflammatory reactions and immune responses. Less